Identification of a Potential Prognostic Signature based on Immune-related Genes in Primary Glioblastoma

Abstract Background: Glioblastoma (GBM) is a common primary brain tumor with a high incidence in adults with malignant and fast-growing biological characteristics. In this study, we explore the immune-related prognosis markers of GBM at the mRNA level.Methods: The sequencing data and clinical information of GBM patients were downloaded from The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA). The differentially expressed genes (DEGs) were calculated between normal tissues from the Genotype-Tissue Expression (GTEx) database and tumor tissues from TCGA and CGGA. We obtained immune genes from the ImmProt database. The intersection of DEGs and immune genes were defined as the immune-related differential genes (IR-DEGs), based on which, survival associated IR-DEGs were determined by multivariate Cox regression analysis. The survival risk score (SRS) was determined for each sample with the top 6 prognostic associated IR-DEGs. One-year, two-year, and three-year potential survival were predicted by the prognosis prediction model established by multivariate and univariate Cox regression. In addition, we performed CIBERSORT in GBM patients with samples from TCGA cohort; association analysis was performed with prognostic IR-DEGs and immune cells. Furthermore, the influence of prognostic IR-DEGs on the brain tumor microenvironment (TME) was validated in single-cell sequencing analysis.Results: We found 301 IR-DRGs in GBM primary tumor compared with normal tissue, and 19 of them could predict the overall survival (OS) more accurately in GBM patients. Six IR-DEGs (PLAUR, TNFSF14, CTSB, SOCS3, PTX3, and FCGR2B) were selected to construct the SRS, with which, GBM patients were divided into two different groups which combined with high and low risk. The SRS was found to be an independent prognostic factor for GBM and could predict GBM patients’ possible survival with an acceptable efficiency. Moreover, the expression of 6 IR-DEGs and their co-expressed IR-DEGs could influence TME and were associated with GBM prognosis.Conclusions: This study identified a potential immune prognostic signature of glioblastoma, which could enhance the prognosis prediction ability for GBM patients. The immune-related-genes in the TME could potentially benefit the immunotherapy development for GBM patients.